Autopsy studies have demonstrated that the foramen ovale is patent in 20 to 35% of the general population.1,2 Although it is generally considered to be an incidental finding, recent clinical studies suggest that the patent foramen ovale (PFO) may serve as an important route for paradoxical embolization.3,4 In addition, hypoxemia due to right-to-left shunting across a PFO may occur in the setting of elevated right heart pressures or decreased right ventricular compliance.5,6 Although contrast echocardiography has been used to identify right-to-left shunting in patients with a suspected PFO,4,7-10 this technique may be limited by its dependence on a right-to-left component of flow and by the small number of cardiac cycles in which to identify such flow. Doppler color flow mapping, which can image flow jets in either direction across an atrial septal defect, 11 also offers the potential to identify flow across a PFO. Thus, we tested the hypothesis that color flow mapping could accurately detect small jets resulting from flow across a PFO.
ASJC Scopus subject areas
- Cardiology and Cardiovascular Medicine